You have three possibilities:
1. to find an amicable solution
2. to involve MOL and if MOL does not solve your problem
3.to file a case in the Court of First Instance
For more information how to settle a Labour issue in court please visit the link giving below:
http://www.gulfnews.com/uaessentials/residentsguide/working_life/10124556.html You can call a toll-free helpline number 800 665, set up by the Ministry of Labour, to lodge and follow up complaints. The hotline works 24/7.The helpline service is available in five languages — English, Arabic, Malayalam, Tagalog and Urdu.
If you are working under a limited contract, you have to fulfill the same. Working under an unlimited contract, you can resign by giving a 4 weeks notice.
For visa cancellation the PRO of your company has to provide your original passport at DNRD. Visa cancellation outside the UAE is not possible. Do not just "disappear", because you never know.......You might ask sooner or later: How can I cancel my visa? Am I banned? Did I get reported as absconded?
During the resignation period of 4 weeks you are entiteled to receive your full pay. In addition, to keep your passport is illegal and the employer should hand over the passport to you immediatley.
As per Article 6 of Federal Labour Law No. 8:
If the employee or the worker or any beneficiary thereof raised a claim concerning any of the rights accruing to any of them according to the provisions of this law, he shall submit a request thereof to the Labour Department. This department shall summon the two parties to the dispute and shall take whatever it deems necessary to settle the dispute amicably. Such a department does not have the right to force any party to accept any solution that he does not desire.
If the amicable settlement is not reached, the said department must within two weeks from the date of submitting the request, submit the dispute to the concerned court. The submission must be accompanied with a note including a summary of the dispute, the arguments of the two parties and the observation of the department. The court shall, within three days from the date of receiving the request, fix a sitting to consider the claim and the two parties shall be notified thereof.
All the best!